Martin Shkreli made a lot of waves challenging the boards of various biotechs and drugmakers a few years ago as a hedge fund manager. Now his rare disease startup, Retrophin, is taking a similarly aggressive approach to M&A. New York-based Retrophin (OTCBB: RTRX) said just after the market closed today that it has made a hostile bid to acquire Point Richmond, CA-based Transcept Pharmaceuticals (NASDAQ: TSPT) at $4.00 per share.